Balanced Softmax Cross-Entropy for Incremental Learning

Deep neural networks are prone to catastrophic forgetting when incrementally trained on new classes or new tasks as adaptation to the new data leads to a drastic decrease of the performance on the old classes and tasks. By using a small memory for rehearsal and knowledge distillation, recent methods have proven to be effective to mitigate catastrophic forgetting. However due to the limited size of the memory, large imbalance between the amount of data available for the old and new classes still remains which results in a deterioration of the overall accuracy of the model. To address this problem, we propose the use of the Balanced Softmax Cross-Entropy loss and show that it can be combined with exiting methods for incremental learning to improve their performances while also decreasing the computational cost of the training procedure in some cases. Complete experiments on the competitive ImageNet, subImageNet and CIFAR100 datasets show states-of-the-art results

Ciencias sociales y representaciones: estudio de los fenómenos representativos y de los procesos sociales : De lo local a lo global

Este artículo se propone examinar la contribución que el estudio de las representaciones sociales ha hecho al campo de las ciencias sociales. El trabajo explora la emergencia de la noción de representación social y/o colectiva en el campo científico en general y luego en las ciencias sociales en particular, para luego dar cuenta de sus propiedades y características. Se describen los “fenómenos representativos” que actúan en la vida social -se elige esta noción frente a la de “representación”- y se traza un estado del campo de estudio de las representaciones sociales y de sus grandes ejes de problematización. Por último, una vez abordado el debate en torno al “representacionalismo”, se propone mostrar la pertinencia y la vigencia del estudio de las representaciones sociales en el contexto de un mundo globalizado.This article aims to examine the contribution that the study of social representations has made to the field of social sciences. The work explores the emergence of the notion of social and/or collective representation in the scientific field in general, and then in the social sciences in particular, to later account for their properties and characteristics. The "representative phenomena" that act in social life -this notion is chosen as opposed to that of "representation" - are described and it’s drawn a state of the field of study of social representations and their major axes of problematization. Finally, once the debate on "representationalism" has been addressed, it is proposed to show the pertinence and validity of the study of social representations in the context of a globalized world.Facultad de Humanidades y Ciencias de la Educació

Aportes del enfoque de las representaciones sociales al campo de la educación

Este artículo examina las relaciones entre el campo de estudio de la educación y el de las representaciones sociales con el propósito de mostrar la pertinencia de los recursos que ofrece el estudio de estas últimas para el análisis de los procesos que se ponen en juego en los diferentes niveles del sistema educativo. Luego de poner en evidencia los lazos históricos y lógicos existentes entre los dos campos, se insiste sobre la necesidad de preservar su especificidad. La autora despeja las líneas directrices según las cuales los dos campos de estudio se reencuentran, basándose en el ejemplo de la situación francesa que ella conoce y cuyos cuadros de análisis pueden ser extrapolados a contextos nacionales y culturales diferentes. Se trata de delinear los esquemas que organizan el sistema educativo y expresan ideologías que definen funciones para responder a las demandas económicas, educativas, democráticas, de la sociedad y de su cambio histórico. Las representaciones sociales dan testimonio de una evolución de las funciones conferidas a la educación y a la escuela, y afectan las concepciones de los roles y oficios de los docentes y de los alumnos. El rol decisivo que desempeñan en la relación entre los distintos actores del sistema educativo es ilustrado con diversos ejemplos. Este examen histórico y documental muestra cómo el enfoque de las representaciones sociales es un instrumento y una mediación en perfecta adecuación con la problemática plural del campo de la educación.The article examines the relations between the field of study of education and the field of study of social representations. Its aim is to show the relevance of the resources offered by the latter to analyse the processes regulating the different levels of the educational system. After having given evidence of the historical and logical links that exist between the two fields, it underlines the importance to preserve their specificities. The author isolates the guidelines that allow the encounter between the two fields, taking into account the French situation that she knows and whose analytic devises can be extrapolated to other na tional and cultural contexts. The purpose is to delineate the schemas that organize the educational system and express ideologies that define its functions in order to fulfil the financial, educational and democratic demands of society and their historical change. Social representations give evidence of an evolution in the functions given to education and school, and have some influence on the conceptions related to teachers and students agency. The important role they play in the relation between the actors of educational system is illustrated by different examples. This historical and documentary examination shows how the social representations approach is an instrument and a mediation corresponding perfectly to the multiple problems tacked in the field of study of education

Propagation of social representations

Based on a minimal formalism of social representations as a set of associated cognems, a simple model of propagation of representations is presented. Assuming that subjects share the constitutive cognems, the model proposes that mere focused attention on the set of cognems in the field of common conscience may replicate the pattern of representation from context into subjects, or, from subject to subject, through actualization by language, where cognems are represented by verbal signs. Limits of the model are discussed, and evolutionist perspectives are presented with the support of field data

Ciências sociais e representações:: estudo dos fenômenos representativos e processos sociais, do local ao global

The purpose of this article is to examine the potential contribution that the study of representations - an approach developed in the field of social psychology - can bring to the social sciences. At the outset, the discussion is based on the observation of the social sciences' emerging interest in the relation between ordinary and scholarly knowledge, the social inscription of cognitive processes, the importance of the notion of "common", the need to reconfigure the relationship among disciplines, and that of considering the complexity of phenomena when addressing them. The examination of the notion of social and/or collective representation within the history of the social sciences, notably in Anthropology, History and Sociology, falls on the recognized properties of representative phenomena and on their roles in social life. The lines of problematization of this study are presented in a table summarizing the research space that concerns them. After discussing the scientific and political critiques of 'representationalism', a scheme that places representative phenomena at the intersection of three spheres: subjective, intersubjective, and transsubjective allows us to show the pertinence of the study of social representations in a globalized space. This pertinence is illustrated by works dealing with the effects of globalization vectors on local social identities, and by the positions adopted by Latin American researchers regarding the importation of models borrowed from the dominant circles of the first world.O objetivo deste artigo é examinar a contribuição que uma abordagem desenvolvida na psicologia social - o estudo das representações sociais - pode trazer às ciências sociais. Como ponto de partida, a reflexão se apoia na constatação do novo interesse desenvolvido nas ciências sociais pelas relações entre o saber ordinário e o saber erudito, a inscrição social dos processos cognitivos, a importância da noção de “comum”, as necessidades de reconfigurar as relações entre disciplinas e considerar a complexidade dos fenômenos abordados. Um exame do tratamento da noção de representação social e/ou coletiva na história das ciências sociais - notadamente na antropologia, na história e na sociologia - recai sobre as reconhecidas propriedades dos fenômenos representativos e sobre seus papéis na vida social. Os eixos de problematização de seu estudo são apresentados em um quadro que resume o espaço de pesquisa que os concerne. Depois de discutir as críticas científicas e políticas dirigidas ao “representacionalismo”, um esquema que coloca fenômenos representativos na interseção de três esferas de pertencimento - subjetiva, intersubjetiva e trans-subjetiva - e permite mostrar a pertinência do estudo das representações sociais em um espaço globalizado. Essa pertinência é ilustrada pelo exemplo de trabalhos relativos aos efeitos dos vetores da globalização sobre identidades sociais locais, e pelas posições adotadas pelos pesquisadores latino-americanos em face da importação de modelos emprestados dos círculos dominantes do Primeiro Mundo. Tradução: José Geraldo de Oliveira Almeid

Ciencias sociales y representaciones: estudio de los fenómenos representativos y de los procesos sociales : De lo local a lo global

Este artículo se propone examinar la contribución que el estudio de las representaciones sociales ha hecho al campo de las ciencias sociales. El trabajo explora la emergencia de la noción de representación social y/o colectiva en el campo científico en general y luego en las ciencias sociales en particular, para luego dar cuenta de sus propiedades y características. Se describen los “fenómenos representativos” que actúan en la vida social -se elige esta noción frente a la de “representación”- y se traza un estado del campo de estudio de las representaciones sociales y de sus grandes ejes de problematización. Por último, una vez abordado el debate en torno al “representacionalismo”, se propone mostrar la pertinencia y la vigencia del estudio de las representaciones sociales en el contexto de un mundo globalizado.This article aims to examine the contribution that the study of social representations has made to the field of social sciences. The work explores the emergence of the notion of social and/or collective representation in the scientific field in general, and then in the social sciences in particular, to later account for their properties and characteristics. The "representative phenomena" that act in social life -this notion is chosen as opposed to that of "representation" - are described and it’s drawn a state of the field of study of social representations and their major axes of problematization. Finally, once the debate on "representationalism" has been addressed, it is proposed to show the pertinence and validity of the study of social representations in the context of a globalized world.Facultad de Humanidades y Ciencias de la Educació

O movimento de retorno ao sujeito e a abordagem das representações sociais

O artigo constata, nas ciências sociais, um retorno à noção de sujeito capaz de inspirar uma nova abordagem da subjetividade no campo de estudo das representações sociais. Após um exame dos momentos que significaram a morte e a ressurreição da noção de sujeito, são abordados os principais temas que caracterizaram a sua reintegração na História, na Sociologia e na Antropologia. Esses temas permitem descartar o risco de uma visão solipsista no exame da parte subjetiva das representações sociais. Para esse fim, um esquema tripartite é proposto, relacionando a gênese e as funções das representações sociais a três esferas (subjetiva, intersubjetiva e transubjetiva) e ilustrado por uma análise dos debates relativos ao célebre episódio das caricaturas de Maomé. As reflexões finais propõem que o estudo das representações sociais se oriente para as relações entre pensamento e mudança social.  &nbsp

Ciencias sociales y representaciones: estudio de los fenómenos representativos y de los procesos sociales : De lo local a lo global

Este artículo se propone examinar la contribución que el estudio de las representaciones sociales ha hecho al campo de las ciencias sociales. El trabajo explora la emergencia de la noción de representación social y/o colectiva en el campo científico en general y luego en las ciencias sociales en particular, para luego dar cuenta de sus propiedades y características. Se describen los “fenómenos representativos” que actúan en la vida social -se elige esta noción frente a la de “representación”- y se traza un estado del campo de estudio de las representaciones sociales y de sus grandes ejes de problematización. Por último, una vez abordado el debate en torno al “representacionalismo”, se propone mostrar la pertinencia y la vigencia del estudio de las representaciones sociales en el contexto de un mundo globalizado.This article aims to examine the contribution that the study of social representations has made to the field of social sciences. The work explores the emergence of the notion of social and/or collective representation in the scientific field in general, and then in the social sciences in particular, to later account for their properties and characteristics. The "representative phenomena" that act in social life -this notion is chosen as opposed to that of "representation" - are described and it’s drawn a state of the field of study of social representations and their major axes of problematization. Finally, once the debate on "representationalism" has been addressed, it is proposed to show the pertinence and validity of the study of social representations in the context of a globalized world.Facultad de Humanidades y Ciencias de la Educació

Class-Incremental Learning using Diffusion Model for Distillation and Replay

Class-incremental learning aims to learn new classes in an incremental fashion without forgetting the previously learned ones. Several research works have shown how additional data can be used by incremental models to help mitigate catastrophic forgetting. In this work, following the recent breakthrough in text-to-image generative models and their wide distribution, we propose the use of a pretrained Stable Diffusion model as a source of additional data for class-incremental learning. Compared to competitive methods that rely on external, often unlabeled, datasets of real images, our approach can generate synthetic samples belonging to the same classes as the previously encountered images. This allows us to use those additional data samples not only in the distillation loss but also for replay in the classification loss. Experiments on the competitive benchmarks CIFAR100, ImageNet-Subset, and ImageNet demonstrate how this new approach can be used to further improve the performance of state-of-the-art methods for class-incremental learning on large scale datasets.Comment: Best paper award at 1st Workshop on Visual Continual Learning, ICCV 202